AFR misleading? Plugs tell a better story?

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On number 3, I checked the plug wire by itself, also then connected to the cap, testing through terminal to spark plug wire end. All seemed good. Going to take a better look at cap inside when I get home. Only focused on #3 will take a second look to see how other terminals look.
Rotor tip is amazingly clean.
 
skidmark said:
Pictures of cap and rotor. Found rotor tip loose, able to go up about 1/16”. Rivet pulled out pretty easy with pocket knife. Don’t remember part number, it’s the extended tip from Napa. Street fire plug wires, checked #3 wire, exterior looks good, resistance is good. I’ve recently read not to run consecutive firing cylinder wires. I have 5 & 7 run side by side, will fix that.
Started leak down testing.

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I've seen a rotor fail like that before. I'm not sure what goes sideways first...the screw/rivet gets loose or the slot the tip sits in allows the tip to move around and starts working on the screw/rivet and then they come loose.

Either way, I've seen it before and it's happened to me and caught me off guard. Usually you see it with higher RPM situations, but in this day and age, junk is junk.

Good catch.
 
My guess is the plug fouled or something else caused resistance and the rotor tip heats up trying to arc across to the cap. Once the rivet heats up, the plastic loosesns up on it. Just a guess but yellow rose is right junk is junk. Just replace it with good quality and move on.
 
mderoy340 said:
A small screw and a drop of epoxy will fix the rotor.
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Sure if you’re in the middle of the desert trying to get home or tying to make the next round without parts, but if you’re in your driveway diagnosing problems trying to eliminate variables I can’t see why you would.
 
TT5.9mag said:
Sure if you’re in the middle of the desert trying to get home or tying to make the next round without parts, but if you’re in your driveway diagnosing problems trying to eliminate variables I can’t see why you would.
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Because the new crap part you replace it with can loosen as well. I've had Standard, Blue Streak brass rotors loosen in the past and the screw/epoxy works.
 
512Stroker said:
Just my 2 cents, but you may be running out of fuel on the top end.
What fuel pump are you using? Fuel pressure at rpm?
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Haven’t seen anything going on.
I have an in tank electric fuel pump with 3/8 supply and return loop, regulated PSI @ a little over 6 PSI. Monitored by in car fuel gauge with remote sensor at regulator.
 
AJ/FormS said:
>The PCV needs to feed into the primaries and dump in the vicinity of the idle discharge port and transfer slots. This promotes good mixing with the low-speed circuit.
>The vacuum booster should attach at the secondary side port, and you must prove that the booster is not constantly sucking air.
.
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Disconnected brake booster hose from manifold, it’s now attached and capped to the rear of carb. Tried a handheld vacuum pump to test brake booster, couldn’t get it to pump up. Not sure if pump is too small. So for now I’ll leave the brake booster capped and disconnected from engine. Thinking it’s bad maybe I’ll go manual master cylinder.
Every time I think I’m going to work on it something comes up. Borrowed a leak tester so hopefully I can do it soon.
Added a valve at inlet to ease up on pressure. Thanks for the info.

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Yeah, that valve will soften the hit, and if you have the piston exactly at TDC-compression, hopefully the piston will stay there. You only have a 2 or 3 degree window, before 80psi ( my test pressure) will push the piston down.
You can use less pressure, but it will be less accurate, because, remember your compression results. Furthermore, when the fuelcharge catches fire and expands,the pressure of those gasses in the chamber are gonna sky-rocket. IDK what the ratio is, and it varies continuously with rpm,throttle-opening, and air-density,etc but I imagine it could be many times the compression test numbers. I'll guess the pressure could, at some point, reach 400psi, I mean it's just a guess. So then my test pressure of 80psi is just 5% of that. and the typical tester calls for 30psi, which is less than 2%.
If you just cannot get the crank to hold still, you can back off the rocker gear, and hook the tester up, which will push the piston to the bottom. This doesn't tell you anything about the condition of the top of the bore, or bad lifters, but it will still tell you about the valves and the rings.
 
I don’t know what happened, I did two rounds of leak testing today. Weird numbers on #1, and a couple of others. I was going to do a third and final test to confirm numbers. When warming up the motor I heard a tick at first I thought it was lifters which always seem to be noisy for a little while. Well it turned into a knock. I’m pretty sure it’s not an exhaust leak. Then I found a small puddle of oil on the floor. Looks like it was pushed out of dip stick. My brother in law has a very small wire camera he’s bringing over tomorrow to look in the cylinders. I’m thinking I should pull the pan. Ugh. Unbelievable. Motor was showing leakage from 3% to 16%
 
skidmark said:
I don’t know what happened, I did two rounds of leak testing today. Weird numbers on #1, and a couple of others. I was going to do a third and final test to confirm numbers. When warming up the motor I heard a tick at first I thought it was lifters which always seem to be noisy for a little while. Well it turned into a knock. I’m pretty sure it’s not an exhaust leak. Then I found a small puddle of oil on the floor. Looks like it was pushed out of dip stick. My brother in law has a very small wire camera he’s bringing over tomorrow to look in the cylinders. I’m thinking I should pull the pan. Ugh. Unbelievable. Motor was showing leakage from 3% to 16%
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3% isn't bad on a cold engine. Even a warm engine with that leak percentage isn't bad.

The 16% is not good. Where's the air going?? Could be head gaskets or something.
 
yellow rose said:
3% isn't bad on a cold engine. Even a warm engine with that leak percentage isn't bad.

The 16% is not good. Where's the air going?? Could be head gaskets or something.
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Will do leak a test tomorrow. Pulled plugs #1 is black. Noise was from the front, was thinking water pump or alternator, but really don’t think they’re making this noise.
 
skidmark said:
Will do leak a test tomorrow. Pulled plugs #1 is black. Noise was from the front, was thinking water pump or alternator, but really don’t think they’re making this noise.
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If your engine really did push out the dipstick and puke oil out you have an internal issue causing a massive amount of blowby (pressure) into the crankcase. This would be directly related to your leakage issue - Piston rings.
 
Looked in #1 cylinder with wire camera, not the best quality.
Couldn’t manipulate it fully soft wire has a mind of its own. Of what I did see, nothing obviously wrong. Going to pull head off.
 
skidmark said:
maybe I’ll go manual master cylinder.
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I am installing a 4 wheel, 6 piston calipers, complete Wilwood disc brakes system, including going to a Wilwood master cylinder.
I'm keeping my brakes MANUAL, and this new system is not a "budget" setup by any means. I'm keeping manual brakes because I prefer actually being able to modulate my brakes, rather than them being more like an on/off switch. I also know there are ways around having low vacuum and how that's bad for power brakes, but once again, the feel of manual brakes is my preference, and that's in a 70 Roadrunner, so more weight to stop than an A body.
Short version: unless you have leg weakness, I'd say don't hesitate to do manual brakes. More room under the hood too!
 
Biomedtechguy said:
I am installing a 4 wheel, 6 piston calipers, complete Wilwood disc brakes system, including going to a Wilwood master cylinder.
I'm keeping my brakes MANUAL, and this new system is not a "budget" setup by any means. I'm keeping manual brakes because I prefer actually being able to modulate my brakes, rather than them being more like an on/off switch. I also know there are ways around having low vacuum and how that's bad for power brakes, but once again, the feel of manual brakes is my preference, and that's in a 70 Roadrunner, so more weight to stop than an A body.
Short version: unless you have leg weakness, I'd say don't hesitate to do manual brakes. More room under the hood too!
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Thanks for the info and good to hear. Going to give it a try. Either a 1” bore or 15/16” For master cylinder.
Aluminum Master Cylinder Part Numbers and Data
 
Looks like the 1” listed in the link posted above is actually 1-1/32”, so I guess I’ll give the 15/16 or 24mm (same size) a try. Also will need to make an adapter plate and push rod for manual MC.
 
skidmark said:
Looks like the 1” listed in the link posted above is actually 1-1/32”, so I guess I’ll give the 15/16 or 24mm (same size) a try. Also will need to make an adapter plate and push rod for manual MC.
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Here's the Wilwood master cylinder I have. 15/16" diameter piston bore. Quick Performance is the vendor.
950-261-13626-bk.jpg

The salesman I've been working with said that bore size master would work well with the slave cylinders in my setup, the calipers are unique in that they are SIX piston calipers on ALL 4 wheels. Anyway he said the combo would provide some good pedal travel, which is desirable to me, and allow for plenty enough force multiplication to lock up all 4 brakes should I press hard enough.
Wilwood 261-13626-BK: Aluminum Tandem Master Cylinder Kit Black E-Coat Finish | JEGS
 
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